Insulating material.



UNITED STATES PATENT onnron.

J'OHN FERLA, OF NEW YORK, N. Y., ASSIGNOR TO AMERICAN MINERAL WOOD MANUFACTURING COMPANY, A CORPORATION OF NEW YORK.

INSULATING MATERIAL.

No Drawing.

To all whom it may concern:

Be it known that I, J OHN FERLA, a citizen of the Republic of Switzerland, residing in New York city, New York, have invented a new and useful Improvement in Insulating Material, of which the following is a specification.

This invention relates to insulating material and it has'for its Object the production of an -insulating material which can be readily cut'and worked with ordinary Woodworking tools, which is comparatively inexpensive to produce, and which is adapted for I use in insulating conductors for electric currents of high potential,

The invention also contemplates the provision of an insulating material which is thoroughly fire-proof and sufficiently strong to withstand rough handling without danger of breakage.

In producing the improved insulating ma terial, I preferably proceed as follows: I take asbestos and hemp, cut and crush them both into very small and fine pieces by means of special cutting machinery and a revolving crusher, then with these ingredients I mix cement (and coloring matter if desired) in the dry state. For this mixing a rotary machine or revolving kettle is preferably employed. The dry mixture ofasbestos, hemp,

cement and coloring matter is then transferred to another mixer where acetic acid, liquid glue and water are added. -The quantity of-water added at this stage is sufficient to moisten the ingredients thoroughly and form a moderately thick paste. The mixture is then transferred to a large tank provided with an agitator to prevent the solid material from settling or becoming hardened and from this tank the pasty mass 1s transferred to a canal where an excess of water is added to make '-the material flow freely. The highly fluid mixture is flowed from the canal upon a moving or revolving web, such as wire cloth. of suitable mesh, in order to allow the excess water to drain out of the material. After the water has been allowed to drain off for a time the material is passed ontoa strip of felt or like material and is subjected to light pressure, preferably through the agency of rollers, which gage the thickness of the sheet of material and also express some of the residual water, which is absorbed by the felt. After the Specification of Letters Patent.

Application filed May 16, 1907.

atented Dec. 21. 1 91 5.

Serial No. 374,044.

material is hardened enough to be handled with safety, it is cut into sheets of the desired dimensions and theseare subjected to heavy pressure in a powerful press, the pressing operation being preferably carried on in a pressure chambenfrom which the air is exhausted in order to facilitate the re moval of the water still remaining in the effect the rapid drying of the oil. The addition of the acetic acid to the mixture prevents the composition from becominghard and brittle with age, and tends to maintain its easily workable characteristics. The acetic acid seems to prevent a kind of petri fication to which mixtures of asbestos and cement are subject afterany considerable" period of time. The asbestos and hemp fibers form, the body of the compound and cement forms a sort of filling medium 'which occupies the spaces among the fibers; It is true that the cement when mixed also serves to some extent as a binder, but this function is mainly performed by the glue and the acid produces a suitable degree of hardness. The. resulting material is characterized by a high degree of electrical non-conductivity, is fireproof, considerably harder than the wood, and yet is adapted to be handled and worked with the tools 'ordinarily employed in woodworking. i

While I preferably employ asbestos, hemp, cement, acetic acid and glue in preparing the material which is subjected to the treatment with oil, the characteristic qualities of my material may be obtained in a measure by the use of asbestos and cement alone in the preparation of the material to be treated with the oil. The material so produced has not the same degree of toughness as when all of the materials above mentioned are employed, and I therefore preferably make use of the additional materials already mentioned; but I do not wish to be understood ing all of the ingredients enumerated,

While it is desirable to heat the asbestos and cement composition before introducing it into the oil and such a preliminary heatingjncreases the effectiveness of the treatment with oil, the composition may be insuitable for use in making the insulating material, it is to be understood that otheroils of similar properties may be employed instead, and it is probable that other drying oils will give satisfactory results. It is also obvious that other binding materials than those which I have mentioned may be used with the asbestos to form the composition which is soaked in oil, and I do not limit myself to the employment of the binding materials specified, though those binding materials give the best results which I have obtained. I

Having thus described my invention, what I claim is new and desire by Letters Patent is:

1. The composition of matter comprising, a mixture of cement,- hemp, mineral fiber,

acetic acid and glue, impregnated'with a drying oil.

2. The process of forming a composition of matter which comprises mixing cement and fibrous material, then adding a liquid gelatinous binder and water to form a liquid paste, removing the surplus water,.impregnating with a drying oil, and then drying or oxidizing said oil. .t

3. The of matter which comprises, mixing cement, hemp and asbestos, then adding water, acetic acid and glue to form a liquid. paste, removing the surplus liquid, impregnating with a drying oil, and then drying or oxidizing said oil.

4. A composition of matter comprising a medium forming a body, a filler and binder, an agent for preventing undue hardening, and a drying oil.

' 5. A composition of matter comprising a medium forming abody, a filler, a binder, an agent for preventing wundue hardening, and a drying oil.

In testimony whereof, I have signed my name in the presence of two witnesses.

JOHN FERLIX Witnesses J. FRANK GUIMARAEZ, WM. BRADFORD.

arocess of :Eormin a com osition 

